/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.iotdb.db.metadata.utils;

import org.apache.iotdb.commons.exception.IllegalPathException;
import org.apache.iotdb.commons.exception.MetadataException;
import org.apache.iotdb.commons.path.PartialPath;
import org.apache.iotdb.db.conf.IoTDBConfig;
import org.apache.iotdb.db.exception.metadata.IllegalParameterOfPathException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.List;
import java.util.Locale;
import java.util.Map;

import static org.apache.iotdb.commons.conf.IoTDBConstant.*;

public class MetaFormatUtils {

    private static final Logger logger = LoggerFactory.getLogger(MetaFormatUtils.class);

    public static String[] RESERVED_NODE_NAMES = {"time", "timestamp"};

    /**
     * check whether the given path is well formatted
     */
    public static void checkTimeseries(PartialPath timeseries) throws IllegalPathException {
        try {
            checkCharacters(timeseries.getFullPath());
        } catch (MetadataException e) {
            throw new IllegalPathException(timeseries.getFullPath(), e.getMessage());
        }
        for (String name : timeseries.getNodes()) {
            try {
                checkNameFormat(name);
                checkReservedNames(name);
            } catch (MetadataException e) {
                throw new IllegalPathException(timeseries.getFullPath(), e.getMessage());
            }
        }
    }

    /**
     * check whether the node name uses "." or "*" correctly
     */
    private static void checkNameFormat(String name) throws MetadataException {
        if (!((name.startsWith("`") && name.endsWith("`")))
                && (name.contains(".") || name.contains("*"))) {
            throw new MetadataException(String.format("%s is an illegal name.", name));
        }
    }

    /**
     * check the characters in path or single node
     */
    private static void checkCharacters(String timeseries) throws MetadataException {
        if (!IoTDBConfig.NODE_PATTERN.matcher(timeseries).matches()) {
            throw new MetadataException(
                    String.format("The name, %s, contains unsupported character.", timeseries));
        }
    }

    /**
     * check whether the node name uses the reserved name
     */
    private static void checkReservedNames(String name) throws MetadataException {
        String processedName = name.trim().toLowerCase(Locale.ENGLISH);
        for (String reservedName : RESERVED_NODE_NAMES) {
            if (reservedName.equals(processedName)) {
                throw new MetadataException(String.format("%s is an illegal name.", name));
            }
        }
    }

    /**
     * check whether the node name is well formatted
     */
    public static void checkNodeName(String name) throws MetadataException {
        checkCharacters(name);
        checkReservedNames(name);
        checkNameFormat(name);
    }

    /**
     * check whether the measurement ids in schema is well formatted
     */
    public static void checkSchemaMeasurementNames(List<String> measurements)
            throws MetadataException {
        for (String measurement : measurements) {
            checkNodeName(measurement);
        }
    }

    /**
     * check whether the storageGroup name uses illegal characters
     */
    public static void checkStorageGroup(String storageGroup) throws IllegalPathException {
        if (!IoTDBConfig.STORAGE_GROUP_PATTERN.matcher(storageGroup).matches()) {
            throw new IllegalPathException(
                    String.format(
                            "The database name can only be characters, numbers and underscores. %s",
                            storageGroup));
        }
    }

    /**
     * check props when creating timeseries
     */
    public static void checkTimeseriesProps(String path, Map<String, String> props)
            throws IllegalParameterOfPathException {
        if (props != null && props.containsKey(LOSS) && props.get(LOSS).equals(SDT)) {
            checkSDTFormat(path, props);
        }
    }

    // check if sdt parameters are valid
    private static void checkSDTFormat(String path, Map<String, String> props)
            throws IllegalParameterOfPathException {
        if (!props.containsKey(SDT_COMP_DEV)) {
            throw new IllegalParameterOfPathException("SDT compression deviation is required", path);
        }

        try {
            double d = Double.parseDouble(props.get(SDT_COMP_DEV));
            if (d < 0) {
                throw new IllegalParameterOfPathException(
                        "SDT compression deviation cannot be negative", path);
            }
        } catch (NumberFormatException e) {
            throw new IllegalParameterOfPathException("SDT compression deviation formatting error", path);
        }

        long compMinTime = sdtCompressionTimeFormat(SDT_COMP_MIN_TIME, props, path);
        long compMaxTime = sdtCompressionTimeFormat(SDT_COMP_MAX_TIME, props, path);

        if (compMaxTime <= compMinTime) {
            throw new IllegalParameterOfPathException(
                    "SDT compression maximum time needs to be greater than compression minimum time", path);
        }
    }

    private static long sdtCompressionTimeFormat(
            String compTime, Map<String, String> props, String path)
            throws IllegalParameterOfPathException {
        boolean isCompMaxTime = compTime.equals(SDT_COMP_MAX_TIME);
        long time = isCompMaxTime ? Long.MAX_VALUE : 0;
        String s = isCompMaxTime ? "maximum" : "minimum";
        if (props.containsKey(compTime)) {
            try {
                time = Long.parseLong(props.get(compTime));
                if (time < 0) {
                    throw new IllegalParameterOfPathException(
                            String.format("SDT compression %s time cannot be negative", s), path);
                }
            } catch (IllegalParameterOfPathException e) {
                throw new IllegalParameterOfPathException(
                        String.format("SDT compression %s time formatting error", s), path);
            }
        } else {
            logger.info("{} enabled SDT but did not set compression {} time", path, s);
        }
        return time;
    }
}
